Opencv-python: Can not create x264 VideoWriter

[hugobordigoni]

Expected behaviour

It would be nice to be able to write x264 (fourcc avc1) video with this opencv install.

Actual behaviour

Currently, I can write mp4v or xvid video but not avc1. The error message is:

[h264_nvenc @ 0x1f159e0] Cannot load libcuda.so.1
Could not open codec 'h264_nvenc': Unspecified error

I don't really know where this libcuda come from.
I tried to install libx264-dev but it did not help.

Steps to reproduce

import cv2
fourcc = cv2.VideoWriter_fourcc(*'avc1')
video = cv2.VideoWriter('test.mp4', fourcc, 30, (1280, 720))

• ubuntu 16.04
• x86
• opencv-python==3.4.0.12

BTW: Thank you so much for this pip package. Not having to build opencv from source is really cool!

[skvark]

x264 encoding falls under GPL license in FFmpeg. Only LGPL licensed builds of FFmpeg are redistributed within opencv-python packages and thus the packages support only x264 decoding since the x264 decoder in FFmpeg is LGPL. Unfortunately you have to do a manual build if you wish to use x264 encoder.

Installing libx264-dev will not help. You can't use global system packages with opencv-python, Python's wheel format is self contained and already includes all the necessary dependencies.

[hugobordigoni]

Ok very clear. Thanks for the info. I'll stick to mp4v.